Do PhD students get summers off?

While graduate students dont really stick by a strict semester/trimester/quarter/summer/etc. schedule, it more or less dictates when you can take vacation. I never took more than a day or two off during Spring Break, and my summers were strictly time to get more work done (or to teach a summer class).

Are PhDs lonely?

Studying on a PhD course is not only an academic challenge, but it can also be rather socially draining. Over the three year course, you will be expected to conduct your research independently and as a consequence of this some students may begin to feel isolated and lonely.